Bioadhesives can be used to seal blood vessels. However, fluid at the site of application, such as blood, may prevent the bioadhesive from working properly. For example, in a vessel, blood may dilute the bioadhesive or wash it away entirely before the bioadhesive has an opportunity to adhere and/or crosslink.
One place it may be useful to use bioadhesives is within vessels, such as blood vessels. For example, spider veins (telangiectasias) are caused when small, superficial blood vessels dilate and rise above the skin surface, appearing most commonly on the face and legs. They can be red, purple or bluish in color, and can appear in noticeable small patches or can cover large areas of skin.
Telangiectasia develops in the legs often due to the presence of venous hypertension within underlying varicose veins or underlying venous reflux disease. Flow abnormalities within the medium sized veins of the leg (reticular veins) can also lead to the development of telangiectasia.
Current treatments for such modalities include the use of commercial sclerosants, e.g., sodium tetradecyl sulfate (STS) and polidocanol, which are injected into the vein and work by damaging the cell lining of blood vessels, causing them to close and eventually be replaced by other types of tissue. Such current treatment can require multiple sessions, and in some case can result in long term staining.
Biomaterial based treatments are also being proposed (but not approved for use) for spider vein treatment. The limitations of biomaterials are uncontrolled degradation of the biomaterial, weak adhesion, and insufficient or slow absorption of the vein into surrounding tissue. Some of these limitations may be caused by blood flowing through the vessel, thereby diluting or washing the biomaterial away before the biomaterial has an opportunity to properly cure. Further, biomaterial based treatments can also suffer from poor cosmetic effects (such as inflammation and necrosis and staining). Accordingly, a need exists for improved formulations that can occlude vessels in a mammal.